Devices which fire multiple projectiles, such as pellets, in a short firing cycle have been attempted with poor result.
Most of these attempts involve loading multiple projectiles into a single barrel to be propelled by a single expulsion of compressed gas. For these projectiles to be launched with considerable velocity, very high gas pressure is required to impart enough force to be shared between projectiles. The more pellets are loaded into a single barrel, the more pressure is required to “share” between the total charge of pellets. This leads to the requirement of inconvenient propellant pressures and poor ballistic performance (high spread) with so many projectiles sharing a barrel. Furthermore, high pressure devices may impart very high muzzle energy to single projectiles, or short charges of projectiles, if loading mechanisms malfunction or are intentionally short loaded.
Some attempts to solve these problems involve the firing of multiple barrels loaded with one or more projectiles per barrel. Again the problem of many projectiles per barrel (greater than two projectiles per barrel) becomes apparent with multiple barreled devices. It is impractical to have very many barrels to achieve a high number of high velocity projectiles per firing cycle. Loading is complicated and gas pressure distribution becomes complicated.